(CNN) -- American swimmer Michael Phelps remains on course for his target of eight Beijing gold medals after winning his third event of the Games, taking the men's 200-meter freestyle in a new world record time -- his third in a row.

Phelps is now just one victory away from holding the record for the most gold medals in Olympic history.

The American's ninth career gold medal also ties him with Mark Spitz, Carl Lewis, Paavo Nurmi and Larysa Latynina for the most in Olympic history.

Racing out of lane six, Phelps quickly surged into the lead and led by a full body length halfway through the second of four lengths.

Phelps was nearly two seconds ahead of the field when he touched in one minute, 42.96 seconds, breaking the mark of 1:43.86 he set at last year's world championships.

He is now three from three in Beijing, keeping him on course to beat Spitz's 36-year-old record of seven golds in a single Olympics.

Phelps will go for his fourth medal and 10th overall on Wednesday in the 200m butterfly, yet another event in which he holds the world record.

As a 19-year-old, Phelps won six golds in Athens, in the 100m and 200m butterfly, the 200m and 400m individual medley and the 4x200m free and 4x100m medley relays.

Don't Miss

Meanwhile Aaron Peirsol, won the men's 100 backstroke, defending his title with a world-record time and extending the United States' dominance of the event.

Peirsol finished in 52.54, lowering his old mark of 52.89 set at last month's U.S. trials. Team-mate Matt Grevers earned the silver in 53.11 with Arkady Vyatchanin of Russia and Australian Hayden Stoeckel tied for the bronze in 53.18.

The Americans have won the men's 100m back at four consecutive Olympics, with Peirsol taking the title at the 2004 Athens Games in a time that was 0.17 seconds slower.

Another American, Natalie Coughlin, won the women's 100m backstroke, to become the first woman in history to defend her title in the event.

Coughlin finished in 58.96 seconds, briefly going under world-record pace at the 50m mark. World record holder Kirsty Coventry of Zimbabwe earned the silver in 59.19 with American Margaret Hoelzer taking bronze in 59.34. Six of the eight finalists swam under the one minute mark.

Coughlin was earning her second medal of the Games, having won a silver in the 4x100m freestyle relay. Coventry was the silver medalist in the 400m individual medley.